Update documentation and clean up (#129)

* cleanup

* clean up file layout

common/util/FileUtil.cpp

@@ -1,6 +1,12 @@
+/*!
+ * @file FileUtil.cpp
+ * Utility functions for reading and writing files.
+ */
+
 #include "FileUtil.h"
 #include <iostream>
-#include <stdio.h> /* defines FILENAME_MAX */
+#include <filesystem>
+#include <cstdio> /* defines FILENAME_MAX */
 #include <fstream>
 #include <sstream>
 #include <cassert>
@@ -55,6 +61,14 @@ std::string file_util::get_file_path(const std::vector<std::string>& input) {
   return filePath;
 }
 
+bool file_util::create_dir_if_needed(const std::string& path) {
+  if (!std::filesystem::is_directory(path)) {
+    std::filesystem::create_directories(path);
+    return true;
+  }
+  return false;
+}
+
 void file_util::write_binary_file(const std::string& name, void* data, size_t size) {
   FILE* fp = fopen(name.c_str(), "wb");
   if (!fp) {